System and technique for making holographic projection screens
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Sep 29, 1992
Grant Date -
N/A
app pub date -
Feb 11, 1991
filing date -
Feb 11, 1991
priority date (Note) -
In Force
status (Latency Note)
Importance
Abstract
A fast, accurate system for manufacturing holographic projection screens. The invention (10) includes a mechanism (28) for moving holographic film (26) along a longitudinal axis thereof in a first direction. A mechanism (12) is provided for directing and maintaining an input beam (22) onto the film (26) as the film (26) is moved. The application of a reference beam (23) is then effective to create an interference pattern on the film (26) with the input beam (22). The mechanism (12) for maintaining the input image at a fixed location on the film includes a polygon shaped mirror mounted to rotate at a rate determined in accordance with the rate of movement of the film. An image stabilization system (40) is also provided which includes a detector (58) for monitoring an interference pattern created by the signal beam and the reference beam. Circuitry (60) is included for providing control signals in response to the detector (58) outputs. A phase shifter (44) induces a phase shift in the reference beam. A phase shifter positioning mechanism (46) adjusts the phase shifter (44) in response to the control signals so that the image is stabilized on the film (26) despite the movement thereof.
First Claim
Other Claims data not available